Is Sonya correct that her contract with the Mexican company is complete when she drops it in the mail?

Question

Quizplus · Accepted Answer

A)Under the UCC,acceptance of a contract is generally effective upon mailing;
however,under the CISG,acceptance is generally effective only upon receipt.
B)Under the UCC,acceptance of a contract is generally effective upon mailing;however,under the CISG,acceptance is generally effective only upon receipt.
C)Under the UCC,acceptance of a contract is generally effective upon mailing;however,under the CISG,acceptance is generally effective only upon receipt.
D)Under the UCC,acceptance of a contract is generally effective upon mailing;however,under the CISG,acceptance is generally effective only upon receipt.
E)Under the UCC,acceptance of a contract is generally effective upon mailing;however,under the CISG,acceptance is generally effective only upon receipt.

Is Sonya Correct That Her Contract with the Mexican Company