How do I answer a word choice question in close reading or comprehension?

When answering close reading questions about word choice one of the easiest ways to think about it is what are the CONNOTATIONS of a word - a fancy way of saying what do the words the author has chosen make you think of. For example the words large, fat, chubby, enormous all have similar meanings but make you think of different things and can be used for different effects.
For example in a question like "explain how the word-choice in lines 3-5 help to create an impression of poverty" you could say: The writers word-choice of 'skinny' has connotations (reminds you) of being unhealthily thin like someone who does not have enough to eat.