This is a correct statement regarding sexually transmitted diseases (STD).

Statement A: Sexually transmitted diseases (STD) are infections transmitted from an infected person to an uninfected person through sexual contact.

Statement B: HIV, HPV and Hepatitis B virus is responsible for STD.

1. Vitamin K deficiency causes excessive bleeding from wounds.

2. If there is deficiency of Vitamin K in your body then you can easily get injury marks on your body or skin.

1. The iris controls the amount of light entering the eye.

2. Iris is the colored part of the eye, which provides pigment to the eyes.

3. It is attached to the ciliary muscle, which contracts and expands to accommodate the required amount of light.

1. Dendrites are projections of a neuron (nerve cell) that receive signals (information) from other neurons.

2. Transfer of information from one neuron to another is achieved through chemical signals and electrical impulses, i.e. electrochemical signals.

Mammals are a common source of fibre.

1. Embers Goat

3. Llama

4. Alpaca