In the following question, a sentence is given with a blank to be filled with an appropriate word. Select the correct alternative out of the four options: I am awful ______ picking vegetables.

Introduction / Context:
This question tests your knowledge of common adjective + preposition collocations in everyday English. The sentence describes someone who is bad at a particular activity, namely picking vegetables. You must choose the preposition that naturally follows the adjective awful in this context, creating a grammatically correct and idiomatic phrase.

Given Data / Assumptions:

• Sentence: “I am awful ______ picking vegetables.”
• Options: for, at, of, as.
• The speaker wants to say that they are very bad at the skill of selecting vegetables.
• We need the preposition that correctly forms a phrase with awful meaning “very bad at something”.

Concept / Approach:
In English, adjectives often take fixed prepositions, and using the wrong one sounds unnatural even if the rest of the grammar is correct. With awful, when we mean “very bad at doing something”, the standard structure is awful at + noun / gerund. Examples include “awful at maths” or “awful at driving”. Therefore, the correct preposition is at. The other options (for, of, as) do not collocate with awful in this meaning and would be marked wrong in an exam.

Step-by-Step Solution:
Identify the adjective: awful, used in the informal sense of “very bad”.Notice that it is followed by a gerund phrase “picking vegetables”, which behaves like a noun.Recall the common pattern: good at, bad at, terrible at, awful at + activity.Insert at into the sentence: “I am awful at picking vegetables.” This sounds natural and correct.Check other options: for, of and as do not form standard collocations “awful for picking vegetables”, “awful of picking”, or “awful as picking vegetables”, so they must be rejected.

Verification / Alternative check:
Compare with similar sentences: “I am terrible at singing,” “She is very good at public speaking,” “They are bad at time management.” In all these examples, the adjective relating to ability is followed by at. Substituting for or of in these sentences would make them sound wrong to native speakers. Thus, the same rule applies to “I am awful at picking vegetables”, confirming that at is the correct choice.

Why Other Options Are Wrong:
For is often used to express purpose or benefit (good for health) and does not fit after awful to indicate lack of skill. Of is used in phrases like afraid of, proud of, capable of, but awful of normally introduces a judgement about someone's behaviour (“It was awful of him to say that”), not a lack of ability. As is used in comparisons or roles (“work as a teacher”) and cannot correctly link awful with an activity. Therefore, none of these prepositions gives the intended meaning of being bad at something.

Common Pitfalls:
Many learners try to guess prepositions based on direct translation from their mother tongue, which often leads to errors. A better strategy is to memorise common adjective + preposition pairs as fixed expressions: good at, bad at, awful at, brilliant at, interested in, keen on, fond of, etc. Once you recognise that awful at is the correct pair for describing poor ability, questions like this become straightforward in exams.

Final Answer:
The correct sentence is: “I am awful at picking vegetables.”