In the following one word substitution question, choose the alternative that best replaces the phrase "killing of birds", that is, the deliberate act of killing birds.

Introduction / Context:
This question focuses on one word substitutions derived from Latin roots that describe the killing of specific living things. The phrase "killing of birds" refers to the deliberate killing of birds, and English uses a specialised term formed from the Latin root for bird combined with the suffix for killing. Recognising this pattern helps in mastering technical and scientific vocabulary.

Given Data / Assumptions:

• The phrase to be replaced is "killing of birds".
• Four options are given, each representing the killing of different entities.
• The correct term must refer specifically to birds.
• You are expected to identify the correct Latin root for "bird".

Concept / Approach:
The word "avicide" is formed from "avis", the Latin for bird, and "-cide", meaning killing. Thus, "avicide" literally means killing of birds. "Herbicide" refers to substances used to kill plants or weeds, "vulpicide" to killing a fox (from "vulpes" meaning fox), and "matricide" to killing one s mother (from "mater"). Only "avicide" correctly combines the idea of birds with the act of killing, making it the right one word substitution.

Step-by-Step Solution:
Step 1: Recognise that "-cide" in all options refers to killing or destruction. Step 2: Focus on each prefix to determine what is being killed in each word. Step 3: Recall that "avi" or "avis" means bird, leading to the term "avicide". Step 4: Connect this with the question phrase "killing of birds". Step 5: Eliminate other options as they correspond to killing plants, foxes, or mothers, not birds.

Verification / Alternative check:
Think of other related words using similar roots. "Aviation" and "aviary" both come from "avis" and are related to birds and flying. This same root appears in "avicide", strongly indicating that it concerns birds. In contrast, "herbicide" is used for weed killing chemicals, and "matricide" appears in discussions of family based crimes. These connections confirm that "avicide" is the only correct choice for killing of birds.

Why Other Options Are Wrong:

• Option A, "Herbicide", is a chemical used to kill unwanted plants or weeds, not birds.
• Option C, "Vulpicide", refers to killing a fox, based on the Latin "vulpes".
• Option D, "Matricide", means killing one s own mother.

Common Pitfalls:
Some students may choose "herbicide" because it is the most familiar term, forgetting that it refers to plants, not animals. Others may recognise "-cide" but ignore the prefix, assuming all options are similar. To handle such questions effectively, always break the word into its parts and identify both what is being killed and the act of killing. Building a small mental list of common roots for animals, plants, and family members will greatly increase your accuracy in one word substitution items.

Final Answer:
The correct one word substitution for "killing of birds" is Avicide, so Option B is correct.