Spot the odd one out from the following structures with reference to the male reproductive system:

1. Rete testis

2. Epididymis

3. Vasa efferentia

4. Isthmus 

Which among the following has 23 chromosomes?

1. Spermatogonia                               

2. Zygote

3. Secondary oocyte                           

4.  Oogonia

The vas deferens receives duct from the seminal vesicle and opens into urethra as

1. epididymis                                           

2. ejaculatory duct

3. efferent ductule                                     

4. ureter

Urethral meatus refers to the

1. urinogenital duct

2. opening of vas deferens into urethra

3. external opening of the urinogenital duct

4. muscles surrounding the urinogenital duct