In the following passage, a word has been left out. Read the sentence carefully and select the correct answer for the given blank out of the four alternatives. "Enterprising skill is the ______________ of a teacher to see the perspective of the entire institution and the inter-relationships among and between its parts."

Introduction / Context:
This question is part of a cloze test that focuses on academic language describing teaching skills. The sentence explains what "enterprising skill" means in the context of a teacher. The blank must be filled with a word that grammatically and semantically fits the phrase "is the ______ of a teacher". The correct choice should convert the adjective "able" into an appropriate abstract noun that represents a quality or capacity.

Given Data / Assumptions:

• The sentence is: "Enterprising skill is the ______________ of a teacher to see the perspective of the entire institution and the inter-relationships among and between its parts."
• Options: able, ably, ability, capable.
• The words around the blank: "is the ... of a teacher".
• The intended meaning is to describe a teacher's capacity to see the wider perspective.

Concept / Approach:
We need an abstract noun that can follow "is the" and precede "of a teacher". The correct structure is "is the ability of a teacher". "Able" and "capable" are adjectives, and "ably" is an adverb, so none of them fit the grammatical structure. Only "ability" is a noun that expresses a measurable skill or capacity and fits naturally in this context.

Step-by-Step Solution:
Step 1: Examine the grammatical frame: "is the ______ of a teacher". A noun is needed after "the". Step 2: Option C, "ability", is a noun meaning the power or skill to do something. Step 3: Option A, "able", is an adjective and cannot fit directly after "the". "The able of a teacher" is wrong. Step 4: Option B, "ably", is an adverb and is also grammatically unsuitable in this position. Step 5: Option D, "capable", is another adjective and again cannot serve as a noun after "the". Step 6: Therefore, the only grammatically and semantically correct option is "ability".

Verification / Alternative check:
Read the full sentence with "ability": "Enterprising skill is the ability of a teacher to see the perspective of the entire institution and the inter-relationships among and between its parts." This sounds natural and clearly conveys the meaning that enterprising skill is the teacher's capacity to see the big picture. Inserting any other option results in ungrammatical or awkward phrases, which confirms that "ability" is correct.

Why Other Options Are Wrong:
Option A: "able" is an adjective and cannot function as the head of a noun phrase after "the". Option B: "ably" is an adverb describing how something is done, not what quality someone possesses. Option D: "capable" is an adjective meaning competent, and does not fit as a noun in the given grammatical frame.

Common Pitfalls:
Students sometimes ignore the words around the blank and focus only on general meaning, which leads them to choose a related but grammatically incorrect word like "capable". Cloze test questions are designed to check both grammar and vocabulary together, so learners should always consider the whole phrase before inserting an option. Recognising patterns like "the ability of" is very helpful in solving such items quickly and accurately.

Final Answer:
The correct word to complete the sentence is ability.