In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives: For a minute, dispel all the mental images and stereotypes; forget the jargon of opening up, flow, nidra, and balance. It is one of the basic ones ________ I lead every class with. Choose the demonstrative that best completes this sentence.

Introduction / Context:
This question tests the correct use of demonstrative words in English, in the sentence "It is one of the basic ones ________ I lead every class with." The context is a yoga teacher describing a fundamental posture. The test taker must choose the word that links "one of the basic ones" with the relative clause, while keeping the overall sentence natural and grammatically correct.

Given Data / Assumptions:

• The incomplete sentence is "It is one of the basic ones ________ I lead every class with."
• The subject is "It", referring to a particular asana or exercise.
• The phrase "one of the basic ones" is plural in meaning but refers to a set of basic asanas.
• The options are "this", "these", "that", "those", and "which".
• The sentence intends to say that this asana is among the basic ones with which the teacher begins every class.

Concept / Approach:
The concept here is the use of demonstrative determiners and relative words. In the structure "one of the basic ones that I lead every class with", the word "that" introduces a restrictive relative clause identifying or describing "the basic ones". It is very common in English to say "one of the things that I like" or "one of the books that I read". Using "that" after "ones" is idiomatic and grammatically correct. Other demonstratives like "this", "these", and "those" normally function as determiners or pronouns, not as relative connectors in this structure.

Step-by-Step Solution:
Step 1: Identify the main structure: "It is one of the basic ones ________ I lead every class with." Step 2: Note that "one of the basic ones" needs a relative clause to specify which ones they are, just as in "one of the students that I teach". Step 3: Test "that": "It is one of the basic ones that I lead every class with." This reads naturally; "that" works as a relative pronoun introducing the clause. Step 4: Test "this": "one of the basic ones this I lead every class with" is incorrect; "this" cannot function as a relative word here. Step 5: Test "these": "one of the basic ones these I lead" is ungrammatical for the same reason. Step 6: Test "those": "one of the basic ones those I lead" is also wrong; "those" does not serve as a relative pronoun. Step 7: Test "which": "one of the basic ones which I lead every class with" is possible in some styles of English, but exam constructions usually prefer "that" after "one of" for naturalness and simplicity. Step 8: Conclude that "that" is the best and most idiomatic choice.

Verification / Alternative check:
We can verify by comparing with similar standard patterns: "It is one of the songs that I always sing", "This is one of the roads that lead to the station", "It is one of the subjects that students find difficult". In each example, "that" introduces a relative clause describing "one of the" set. Using the same pattern in the given sentence gives "one of the basic ones that I lead every class with", which fits perfectly. While "which" can also introduce relative clauses, exam-oriented usage often favours "that" in restrictive type clauses without a comma.

Why Other Options Are Wrong:
"this" functions as a demonstrative for singular nouns, as in "this book", and cannot introduce the relative clause in this structure. "these" is a plural demonstrative but again acts as a determiner or pronoun, not as a connector for a relative clause after "ones". "those" is similar to "these" and does not form the expected pattern "ones those I lead every class with". "which" is grammatically possible but is less preferred in such exam sentences after "one of the ones", especially in modern, less formal usage where "that" has become the default relative pronoun for restrictive clauses.

Common Pitfalls:
Students sometimes confuse the roles of demonstratives and relatives and may try to use "these" or "those" after "ones". Others overuse "which" in all relative clauses because they see it often in reading passages. It is important to remember that "that" is the normal choice for restrictive clauses in everyday English, especially after general noun phrases like "one of the things", "one of the reasons", or "one of the basics". Paying attention to authentic examples will help avoid such confusion.

Final Answer:
The correct word to complete the sentence is that, giving "It is one of the basic ones that I lead every class with".