Final answer:
Increasing temperature during hybridization from 65°C to 75°C 2) lowers stringency, promoting the annealing of less complementary DNA strands and possibly leading to more non-specific binding.
Step-by-step explanation:
An increase in temperature from 65°C to 75°C during hybridization will lower stringency. In the context of molecular biology, stringency refers to the conditions that affect the annealing of complementary DNA strands. High stringency corresponds to conditions that promote binding of only highly complementary strands, while lower stringency allows for more mismatches between strands. Raising the temperature hence increases the kinetic energy of the DNA molecules, leading to a decrease in the stability between annealed strands and allowing strands with less complementarity to hybridize. Thus, lowering the stringency could result in more non-specific binding.