A vaccine is a substance that contains all or part of a noninfectious version of a disease-causing organism. When the vaccine is administered to a person, the person's immune system attacks the noninfectious version of the organism and learns to recognize its surface proteins. The next time the immune system comes in contact with the same surface proteins, it has a defense already prepared in order to respond quickly to the invading organism. In this way, a vaccine gives people immunity to the disease-causing organism. Vaccines can be life-saving, but there have been a few cases of people catching a disease from the administered vaccine. How might genetically engineered organisms solve this problem?

GMOs can be used to produce cheaper, easier to administer, and safer vaccines

Explanation:

Genetically modified organisms (GMOs) are organisms whose genomes have been altered in the laboratory by using genome engineering techniques. These GMOs have a fundamental role in clinical research and they have been increasingly used in the last decades for developing safer and cheaper vaccines. For example, ​genetically engineered hepatitis B vaccines have been developed with recombinant DNA techniques using genetically modified yeast (Saccharomyces cerevisiae). Moreover, GMO plants are nowadays also being used to develop consumable vaccines which can be orally administered to be absorbed and assimilated through digestion.

it has one origin of replication, but it proceeds in two directions - d)

the darker peppered moth species were favored due to the fact that the industrial revolution had made all the nearby trees a darker color instead of white.