Which of the following is not an advantage of artificial insemination?

The question asks which option is not an advantage of artificial insemination (AI). Three of the options are well-established benefits:

• Good qualities of exotic breeds are obtained cheaply - semen from genetically superior bulls (often imported breeds) can be shipped to farms at a fraction of the cost of importing the live animal.
• Semen from one bull can be used to serve many cows - a single ejaculate can be diluted and divided into hundreds of doses, dramatically extending one male's reproductive capacity.
• Selected males are used extensively - AI allows the widest possible use of bulls with proven genetic merit, accelerating herd improvement across an entire region.

"Infectious diseases are widely transmitted" is not an advantage - it is a potential disadvantage or risk of artificial insemination. If semen is collected from an infected bull and not properly screened, diseases such as brucellosis, trichomoniasis, or bovine viral diarrhoea can be spread to every cow that receives that semen. In fact, one of the precautions taken in AI programmes is rigorous health testing of donor bulls precisely to prevent this.