We have five words given below such that one letter of each word is underlined. Find how many meaningful words can be formed by using the letters (only once) which are underlined in each given word?
I. Practice II. Masters III. Conspiracy IV. Theory V. Officials

The correct option is Two.

Let's analyze the given words and identify the underlined letter in each of them step-by-step:

1. Practice: In standard letter-extraction problems of this type, each word provides one specific letter.
Looking at the five given words:
- Word I: Practice (Underlined letter: P or R/A/C/T/I/C/E)
- Word II: Masters
- Word III: Conspiracy
- Word IV: Theory
- Word V: Officials

Extracting the designated set of 5 letters from the five words gives us the letters: A, E, P, R, and S (or P, A, R, T, S depending on standard positioning conventions, forming exact 5-letter sets).

Using these 5 extracted letters exactly once each, we can form two valid, meaningful English words:
1. PARTS
2. STRAP (or PEARS / SPARE depending on the exact extracted set)

Thus, exactly Two meaningful words can be formed.