Which part of the constitution is the basis for this diagram

Option D, the Necessary and Proper Clause, is the right answer.  

By contrast, the Necessary and Proper Clause clearly grants incidental authorities upon Congress. This Necessary and Proper Article is sometimes called the elastic clause. This clause comes under the section VIII of the Article I, in the constitution of the United States. The Necessary and Proper clause empowered the Congress to enact the regulations required for the performance of its other authorities instituted by the Constitution. For instance, to direct Commerce with different Nations, and among various states, and with Indian tribes comes under the Necessary and Proper Clause.  

D. The necessary and proper clause

Explanation:

This clause is found in Section 8 of Article I of the U.S. Constitution and it holds that the government has the power to make laws that are deemed to be necessary and proper for carrying into execution the powers specifically granted to it in the Constitution (The Expressed Powers). The power to regulate commerce between states is one of those expressed powers, however, the Constitution does not say anything about the way the government should regulate it, therefore one of the many decisions it can make is to build highways to allow commercials goods to be moved.

the answer is the government.