Red rust of Tea is caused by

Options

A. Puccinia
B. Ustilago
C. Cephaleuros
D. Harveyella.

Answer

### Step-by-Step Solution:

1. **Understanding the Disease**: The question asks about the cause of "red rust of tea," which is a disease affecting tea plants.

2. **Identifying the Causative Agent**: The red rust of tea is specifically caused by a type of algae. It is important to note that this is an algal disease.

3. **Phylum Classification**: The algae responsible for this disease belong to the phylum Chlorophyta. This classification helps in understanding the biological grouping of the organism.

4. **Naming the Alga**: The specific alga that causes red rust in tea is called **Cephalurus**. This is a green alga that infects the tea plant.

5. **Symptoms of the Disease**: The symptoms of red rust include the appearance of round, rusty lesions on the leaves of the tea plant. These lesions can be visually identified as orange or rusty spots.

6. **Favorable Conditions for Disease Development**: The disease tends to occur under certain environmental conditions, particularly high temperature and humidity. These factors create a conducive environment for the growth of the algae.

7. **Final Answer**: Therefore, the correct answer to the question "Red rust of tea is caused by" is **Cephalurus**, which is a green alga.