Question

what is scrotum? and what is vasectomy and tubectomy?

Answer 1

The scrotum is a part of the external male genitalia located behind and underneath the penis.
vasectomy.  is a surgical procedure for male sterilization and/or permanent birth control. During the procedure, the male vasa deferentia are severed and then tied/sealed in a manner so as to prevent sperm from entering into the seminal stream (ejaculate) and thereby prevent fertilization from occurring.
tubectomyis a surgical procedure for sterilization in which a woman's fallopian tubes are clamped and blocked, or severed and sealed, either method of which prevents eggs from reaching the uterus for fertilization.

Answer 2

scrotum is the external part of the body below the lower abdomen 
it is the site in which the testis is been placed as because a lower temp than the body temp is required for production of sperms

vasectomy is the contraceptive methods in male 
that is the cutting and putting knot in the vas deferens to block the way of flow of sperms 

tubectomy is the contraceptive method in female that is the cutting the oviduct or the fallopian tube to block the fusion of gametes and stop of restrict fertilisation