The question is asking to match different types of grass (List I) with the corresponding country (List II) where it is commonly found.

In List I, the types of grass mentioned are:

A. Llanos

B. Prairies

C. Pampas

D. Downs

List II mentions the countries where these types of grass are commonly found:

1. Australia

2. Venezuela

3. USA

4. Argentina

To match the types of grass with the corresponding countries, we need to look for the correct combination of letters from List I and numbers from List II.

Looking at the options provided:

Option 1: Match A with 1, match B with 4, match C with 3, match D with 2.

Option 2: Match A with 1, match B with 3, match C with 4, match D with 2.

Option 3: Match A with 2, match B with 4, match C with 3, match D with 1.

Option 4: Match A with 2, match B with 3, match C with 4, match D with 1.

The correct answer is option 4.