Recall the definition of heat capacity (thermal capacity).

Heat capacity of a body is the amount of heat required to raise the temperature of the entire body by $1^\circ C$ (or $1\,K$).

Mathematically, $C = \frac{Q}{\Delta T}$ So if $\Delta T = 1^\circ C$, then $Q = C$

Interpret the statement in the question.

The question asks:

Heat given to a body which raises its temperature by $1^\circ C$ is what?

This is exactly the definition of the thermal capacity (heat capacity) of the body.

Check the options.

• A: water equivalent — This is the mass of water having the same heat capacity as the body, not the heat itself.
• B: thermal capacity — Correct. This is the heat needed to raise the body's temperature by $1^\circ C$.
• C: specific heat — This is the heat required to raise the temperature of unit mass of a substance by $1^\circ C$.
• D: temperature gradient — Unrelated here.

Conclusion

The correct answer is: $\boxed{\text{B: thermal capacity}}$

Comparison with stored correct answer

Stored correct answer: B

My derived answer: B

Hence, they agree.