(A): In the aluminothermic process, $\mathrm{Al}$ reduction increases the heat of the reaction.

(R) : During reduction in thermit process, $\mathrm{A}{l}_2{\mathrm{O}}_3$ is formed which is an exothermic product.

In aluminothermic process,$\mathrm{Al}$ oxidises to give $\mathrm{A}{l}_2{\mathrm{O}}_3$. It acts as a reducing agent. Hence, A is false.

During reduction in the thermit process, $\mathrm{A}{l}_2{\mathrm{O}}_3$ is formed which is an exothermic, product. This is true.

Therefore, Option D is the correct answer.