A series of planets is given with one term missing. Choose the correct alternative that will complete the series: Jupiter, ?, Uranus, Neptune.

Introduction / Context:
This question uses a simple series based on the names of planets in our Solar System. You are given three planets with one missing in the middle and asked to identify the missing one. Even though it appears to be a general knowledge question, the underlying pattern is just the standard order of the outer planets by increasing distance from the Sun.

Given Data / Assumptions:
- Given series: Jupiter, ?, Uranus, Neptune.
- The options are: Saturn, Earth, Pluto, Mercury.
- We assume the pattern uses the conventional order of planetary orbits from the Sun outward.

Concept / Approach:
The classical order of the major planets from the Sun is: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. In this sequence, Jupiter is followed by Saturn, then Uranus, then Neptune. The series in the question is therefore taking a consecutive slice from the outer planets starting at Jupiter. Identifying this standard astronomic order allows you to fill the missing term easily.

Step-by-Step Solution:
Step 1: Recall the planetary order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Step 2: Locate Jupiter in this sequence. Immediately after Jupiter comes Saturn, then Uranus, then Neptune. Step 3: Match this with the question: Jupiter, ?, Uranus, Neptune. The missing planet between Jupiter and Uranus is therefore Saturn. Step 4: Check that “Saturn” is indeed one of the options provided.

Verification / Alternative check:
Check each option against the Solar System order:
- Earth and Mercury both lie inside the orbit of Jupiter and therefore cannot appear between Jupiter and Uranus in an outward sequence.
- Pluto is not part of the traditional eight major planets and, in any case, lies beyond Neptune, not between Jupiter and Uranus.
Only Saturn correctly fits between Jupiter and Uranus in the standard planetary ordering.

Why Other Options Are Wrong:
- Earth: placed earlier in the sequence than Jupiter, so it cannot appear after Jupiter where the blank is.
- Pluto: considered a dwarf planet and located beyond Neptune, so it does not fit the pattern of the given four consecutive outer planets.
- Mercury: the innermost planet, far inside Jupiter’s orbit; it cannot logically fill the gap between Jupiter and Uranus.

Common Pitfalls:
The main risk is either forgetting the correct order of planets or mixing up inner and outer planets. Some candidates might be tempted by Pluto due to its association with the outer Solar System. To avoid such confusion, memorise the eight major planets in order and recognise that Jupiter, Saturn, Uranus and Neptune form a neat consecutive group of outer gas and ice giants.

Final Answer:
The missing planet in the series is Saturn, giving the complete sequence: Jupiter, Saturn, Uranus, Neptune.