Is csc's refusal to sign a visa a breach of contract?

This is a breach of contract. The National Scholarship Fund Committee clearly stipulates the relevant clauses of breach of contract and punishment in the Agreement on State-sponsored Study Abroad: if an overseas student violates the signed study abroad agreement and other relevant laws, regulations and provisions, the National Scholarship Fund Committee will have the right to take measures such as stopping scholarships, terminating the qualification of state-sponsored study abroad and requesting to return to China within a time limit according to the facts, circumstances and consequences of his breach of contract, according to the relevant laws and regulations of the State and the relevant provisions of the National Scholarship Fund Committee. Refusal to sign a visa is a failure to finish school without justifiable reasons, so it is regarded as a breach of contract.