Instruction: Analyze the query and product title to assess the level of relevance between them, and then output the corresponding option that best describes this relevance.

Input:
Query: electric water heater 50 gallon
Product: Rheem RTEX-18 18kW 240V Electric Tankless Water Heater, small, Gray

Options:
A: The product is relevant to the query, and satisfies all the query specifications.
B: The product is somewhat relevant. It fails to fulfill some aspects of the query but the product can be used as a functional substitute.
C: The product does not fulfill the query, but could be used in combination with a product exactly matching the query.
D: The product is irrelevant to the query.
Answer: B: The product is somewhat relevant. It fails to fulfill some aspects of the query but the product can be used as a functional substitute.