The correct answer is option 'C' - Both 1 and 2.

Explanation:

1. Bio-magnification of DDT:
Bio-magnification refers to the process of increasing concentration of a substance as it moves through the food chain. DDT (dichlorodiphenyltrichloroethane) is a synthetic pesticide that was widely used in the past for its insecticidal properties. DDT is highly persistent and does not easily break down in the environment. When DDT is released into water bodies, it can be absorbed by algae and plankton. These organisms are then consumed by small fish, which are in turn eaten by larger fish. As DDT moves up the food chain, each predator accumulates higher concentrations of the pesticide. This process is known as bio-magnification.

Fish-eating birds and humans are higher up in the food chain and are therefore more likely to be exposed to higher concentrations of DDT. This bio-magnification of DDT from water to fish-eating birds and humans has been well-documented and has led to concerns about the impact of DDT on these organisms.

2. Effects of DDT on hormones:
DDT has been found to have endocrine-disrupting properties, meaning it can interfere with the normal functioning of hormones in the body. Specifically, DDT is known to depress the activity of estrogen, the female sex hormone, and testosterone, a male sex hormone.

Estrogen plays a crucial role in the development and regulation of female reproductive organs and secondary sexual characteristics. Testosterone, on the other hand, is responsible for the development and maintenance of male reproductive tissues and secondary sexual characteristics. Disruption of these hormones can have significant effects on reproductive health and overall hormonal balance.

Studies have shown that exposure to DDT can lead to alterations in hormone levels, decreased fertility, and reproductive disorders in both animals and humans. The specific mechanisms through which DDT affects hormone activity are still being studied, but it is believed that DDT can interfere with hormone receptors and disrupt hormone synthesis and metabolism.

In conclusion, both statements are correct. DDT has been found to bio-magnify from water to fish-eating birds and humans, leading to higher concentrations in these organisms. Additionally, DDT is known to depress the activity of estrogen and testosterone, which can have significant effects on reproductive health.