Question

Insulation was fitted to ________ further heat loss from the building.

• A. guard
• B. protect
• C. save
• D. prevent

Hint:

Look for the verb that takes heat loss directly without a preposition.

Answer 1

The Correct Option is D

This is a collocation question, checking which verb naturally pairs with "heat loss" in standard English usage. Insulation is a physical barrier added to a building specifically to stop energy escaping as heat, so the sentence is describing its purpose.

Among the four choices, "prevent" is the only verb that combines with a noun phrase like "further heat loss" without needing a linking preposition. "Guard" and "protect" both usually pair with "against" or "from" when used this way, for instance "protect against heat loss," so using them without that preposition sounds unnatural and grammatically incomplete. "Save" is used with things you want to preserve or keep, such as "save energy" or "save money," not with something negative you want to stop.

Because "prevent" alone completes the sentence correctly in both meaning and structure, option 4, prevent, is the right choice.