Option 1 states that both statement I and statement II are true, and statement II is the correct explanation of statement I.

Statement I states that the rich sculptural tradition of Mathura is distinguished by its principal medium, the white spotted red sandstone. This means that the sculpture in Mathura is known for being created using white spotted red sandstone.

Statement II states that the white spotted red sandstone is locally available in the Mathura region. This means that the sandstone used for sculpting in Mathura is found in the local area.

Option 2 states that both statement I and statement II are true, but statement II is not the correct explanation of statement I. However, since statement II explains the local availability of the sandstone, it can be considered as the correct explanation for why the rich sculptural tradition in Mathura uses white spotted red sandstone.

Option 3 states that statement I is true, but statement II is false. However, this contradicts the fact that the white spotted red sandstone is indeed locally available in Mathura, as stated in statement II. Therefore, option 3 is not the correct answer.

Option 4 states that statement I is false, but statement II is true. However, statement I is correct in stating that the