In the following spelling question, four versions of the same word are given; select the correctly spelt form of the word that refers to trees bearing cones and needle like leaves.

Introduction / Context:
This question tests spelling of a specific English adjective often used in geography and biology, namely the word that describes trees such as pine, fir, and spruce. Correct spelling is very important in descriptive questions, essays, and professional communication, so examiners regularly include such items to assess attention to detail.

Given Data / Assumptions:
You are given five similar looking options based on the word for cone bearing trees: coniferous, coniferos, coniferrous, coniferros, and conniferous. Only one of these is standard and accepted in good dictionaries. The others are deliberate distortions that add extra letters, remove letters, or change double and single consonants in confusing ways.

Concept / Approach:
The base noun is conifer, which refers to a cone bearing tree. The corresponding adjective is formed by adding the suffix ous to the base. When you add ous to conifer, you do not double any consonants or remove vowels. The resulting standard spelling is coniferous. Any variant that changes this structure by doubling r or n or dropping the final vowel is incorrect.

Step-by-Step Solution:
Step 1: Identify the base word conifer, which you may have seen in phrases like conifer forests or conifer belt.Step 2: Recall that the common adjectival suffix is ous, as in famous, dangerous, and spacious.Step 3: Attach ous directly to conifer to get coniferous without changing the spelling of the base word.Step 4: Compare this correct form with each option and select the one that exactly matches coniferous.Step 5: Confirm that none of the other options match the standard dictionary form.

Verification / Alternative check:
You can check by pronouncing the word slowly in syllables: co ni fer ous. The spelling coniferous mirrors this pronunciation and structure. Looking up a reliable dictionary will also confirm that coniferous is the accepted form used in academic and scientific writing, especially when describing vegetation zones in geography questions.

Why Other Options Are Wrong:
coniferos drops the final u, which breaks the standard suffix. coniferrous doubles the letter r unnecessarily and looks like a mixture of conifer and ferrous. coniferros not only doubles r but also changes the ending to eros, which is not the correct suffix. conniferous doubles the letter n, altering the base word conifer. These are all typical distractors that test if you can distinguish subtle spelling differences.

Common Pitfalls:
A common mistake is to assume that scientific sounding words must have double consonants or very complex spellings. In reality, many such words follow simple and regular patterns. Another pitfall is to focus only on the ending and ignore whether the base word has been altered. Always identify the root and the suffix separately when judging spellings.

Final Answer:
The correctly spelt word describing cone bearing trees is coniferous.