Which of the following is true regarding the resistance of bacteria to antibiotics?

• A. Bacterial resistance to antibiotics only occurs through spontaneous mutations and not by gene transfer.
• B. Bacterial resistance to antibiotics can result from the acquisition of resistance genes through horizontal gene transfer.
• C. All bacteria are naturally resistant to all antibiotics.
• D. Once a bacterium becomes resistant to one antibiotic, it is automatically resistant to all antibiotics.

Answer: (B)

Verified step by step guidance

1. Understand the concept of bacterial resistance to antibiotics, which can arise through different mechanisms including spontaneous mutations and horizontal gene transfer.
2. Recall that spontaneous mutations are random changes in the bacterial DNA that can sometimes confer resistance to an antibiotic, but this is not the only way resistance develops.
3. Recognize that horizontal gene transfer allows bacteria to acquire resistance genes from other bacteria, which can spread resistance traits rapidly within bacterial populations.
4. Evaluate the incorrect statements: not all bacteria are naturally resistant to all antibiotics, and resistance to one antibiotic does not necessarily mean resistance to all antibiotics.
5. Conclude that the true statement is that bacterial resistance to antibiotics can result from the acquisition of resistance genes through horizontal gene transfer.