Answer:
The dialogue would be correct in the following way:
"Are you afraid of snakes?" asked Henry.
Explanation:
The sentence starts with a quote, which must appear between parentheses.
The first letter of a sentence must be capitalized.
The quote is an interrogative sentence, and as such it must end with a question mark.
The final parentheses appears right after the question mark, and there is no need for any additional punctuation.
"Henry" is a proper noun, and as such it must be capitalized.
The sentence must end with a "period" (.).