Answer

Correct option: (ii) Modify the sensor signal for ADC

Explanation

Signal conditioning prepares a raw sensor signal so that it is suitable for accurate measurement and conversion by an ADC.

Common signal-conditioning operations include:

• Amplification – increases a weak sensor signal.
• Filtering – removes unwanted noise and interference.
• Isolation – protects circuits and reduces ground-loop problems.
• Linearization – improves the relationship between sensor output and measured quantity.
• Level shifting – adjusts the signal to the ADC input range.

For example, if a sensor produces 0–100 mV while an ADC accepts 0–5 V, an amplifier can increase the sensor signal before conversion.

Therefore, the correct answer is (ii).