___________ litmus paper turns __________ under acidic conditions and __________ litmus paper turns ___________ under basic or alkaline condition.

Options

A. Red, blue, light blue, red
B. Red, light Blue, red, blue
C. Light Blue, red, red, blue
D. Light Blue, red, blue, red

Answer

To answer the question, we need to fill in the blanks regarding the behavior of litmus paper in acidic and basic conditions.

1. **Identify the behavior of blue litmus paper in acidic conditions**:
- Blue litmus paper turns red when placed in an acidic solution.
- Therefore, the first blank should be filled with "blue" and the second blank with "red".

2. **Identify the behavior of red litmus paper in basic conditions**:
- Red litmus paper turns blue when placed in a basic (or alkaline) solution.
- Therefore, the third blank should be filled with "red" and the fourth blank with "blue".

Putting it all together, the completed statement is:
"**Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic or alkaline conditions.**"

### Step-by-Step Solution:
1. **Determine the effect of acidic conditions on blue litmus paper**:
- Blue litmus paper turns **red** in acidic conditions.

2. **Determine the effect of basic conditions on red litmus paper**:
- Red litmus paper turns **blue** in basic or alkaline conditions.

### Final Answer:
"**Blue litmus paper turns red under acidic conditions and red litmus paper turns blue under basic or alkaline conditions.**"