Soln:

The tube that joins the testes to the urethra is known as the Vas deferens. The vas deferens is a coiled conduit that transports sperm from the epididymis to the urethra and ejaculatory duct. The duct that transports sperm from the testis to the body cavity is known as the Vas deferens. The ducts that transport urine from the kidneys to the urinary bladder are known as ureters. The urethra, which comes from the urinary bladder and opens to the outside, is the common channel for the transmission of urine and sperms in males.

So, the correct answer is (a) testis → vas deferens → urethra