Concept:The correct word must fit an uncountable noun in an interrogative sentence.
Explanation:The sentence asks about an unknown quantity of chalk, which is uncountable.
"Any" is used in questions and negative statements for uncountable or plural nouns.
"A" is wrong because it needs a singular countable noun.
"Many" is wrong because it is used only with countable plural nouns.
"Plenty" is not suitable because it usually requires "of" and is not used directly in this question form.
Thus, "Is there any chalk in the classroom?" is the correct sentence.
Answer:B. any