Question

In the combustion of ethane, what is/are the reactant(s)?

Answer 1

Organic matter usually produce Carbon Dioxide and Water as its products. 
Answer is A for products.
Reactants will be ethane and oxygen
Ethane has 2 carbons. so B is the answer.

Answer 2

Reactant are those that combine or reacts to give products !!

so in combustion of ethane ; ethane and o2 are reactants so ... your answer is B !!