Lichen is the association of :

Options

A. Alga and alga
B. Alga and roots of higher plants
C. Alga and fungus
D. Fungus and fungus

Explanation

To solve the question "Lichen is the association of:", we need to identify the components that make up lichen. Here’s a step-by-step breakdown:

### Step 1: Understand what Lichens are
Lichens are a unique biological entity formed by the symbiotic association between two different organisms.

### Step 2: Identify the components of Lichens
The two main components of lichens are:
- **Fungi**: This is the fungal partner that provides structure and stability to the lichen.
- **Algae**: This is the photosynthetic partner that produces food through photosynthesis.

### Step 3: Analyze the options provided
Now, let’s look at the options given in the question:
- Option A: Algae
- Option B: Algae and roots of higher plants
- Option C: Algae and Fungus
- Option D: Fungus and Fungus

### Step 4: Eliminate incorrect options
- Option A (Algae) is incorrect because it does not mention the fungal partner.
- Option B (Algae and roots of higher plants) is incorrect because roots of higher plants are not involved in the formation of lichens.
- Option D (Fungus and Fungus) is incorrect because it does not include the algal partner.

### Step 5: Select the correct option
The only option that correctly identifies the association in lichens is:
- **Option C: Algae and Fungus**

### Final Answer
Thus, the correct answer is **Option C: Algae and Fungus**.

---