In pair production, the type of photon used:

Explanation

In pair production, a high-energy photon interacts with a nucleus to transform into a particle and its antiparticle, such as an electron and a positron. Gamma rays, being high-energy photons, possess the necessary energy for this process. Option A is incorrect because alpha particles are Helium nuclei, not photons. Option B is incorrect because beta particles are fast-moving electrons or positrons, not photons. Option C is incorrect because while X-rays are photons, they generally do not have sufficient energy for pair production unless they are exceedingly high energy. Option D is correct as gamma rays have sufficient energy to facilitate pair production.