Correct Answer: A

Rationale: The correct answer is A, Sucrose. Sucrose is a disaccharide composed of one molecule of glucose and one molecule of fructose. When glucose and fructose combine, they form sucrose. Choice B, Fructose, is a monosaccharide, not a disaccharide. Choice C, Glucose, is also a monosaccharide, not a disaccharide. Choice D, Galactose, is another monosaccharide and not a disaccharide.

Correct Answer: A

Rationale: The correct answer is A, Shelf fungus. Shelf fungus reproduces via spore formation. Spores are tiny, reproductive cells that are released into the environment to be carried by air or water, allowing the fungus to spread and reproduce. The other choices are incorrect because Lemon tree reproduces via seeds, Smallmouth bass reproduce sexually through the fertilization of eggs by sperm, and Staphylococcus bacteria reproduce by binary fission, dividing into two identical daughter cells.

Correct Answer: C

Rationale: Commensalism is a relationship between two species in which one benefits without affecting the other species. In this scenario, the cattle egrets benefit from the insects stirred up by cattle while the cattle are not significantly impacted by the presence of the egrets. The egrets obtain food easily, and the cattle are neither harmed nor helped by the egrets' presence, making it an example of commensalism. Mutualism involves both species benefiting, parasitism involves one species benefiting at the expense of the other, and competition involves both species being negatively affected by their interactions, none of which apply to the relationship between cattle and cattle egrets in this context.

Correct Answer: A

Rationale: In nature, water vapor becomes liquid water through the process of condensation. Condensation occurs when water vapor cools and changes its state from a gas to a liquid, forming droplets that we commonly see as water droplets on surfaces or clouds in the sky. Sublimation refers to the transition from a solid to a gas without passing through the liquid phase. Precipitation is the process where water in the atmosphere falls to the ground as rain, snow, sleet, or hail. Absorption is the process of one substance being taken in by another.

Correct Answer: A

Rationale: The anther is the part of the flower that produces pollen. It is located at the tip of the stamen, the male reproductive organ of a flower. The anther contains pollen sacs where pollen grains are produced. The style is the part of the pistil that connects the stigma to the ovary, playing a role in pollen tube growth. The stigma is the part of the pistil that receives pollen during fertilization. The pistil is the female reproductive organ of a flower, consisting of the stigma, style, and ovary, and does not produce pollen.