Statement — “Lack of stimulation in the first four to five years of life can have adverse consequences.”\nAssumptions:\nI. A large part of observed intelligence develops in the earliest years of life.\nII. About 50% of measurable intelligence at age 17 is predictable by age four.

Introduction / Context:
The statement ties early-life stimulation to later outcomes. It presupposes that early years are critical for cognitive development, but it need not rely on a specific percentage or test statistic.

Given Data / Assumptions:

• Statement: Lack of stimulation in years 0–5 can lead to adverse consequences.
• Assumption I: A substantial portion of intelligence develops early.
• Assumption II: A precise 50% of intelligence at 17 is predictable by age four.

Concept / Approach:
Assumptions should be necessary, not hyper-specific. The statement needs the general criticality of early years (I), not an exact quantitative claim (II).

Step-by-Step Solution:
1) If early years were not crucial, lack of stimulation would not be especially harmful.2) Therefore I is necessary.3) The 50% figure in II is an illustrative statistic; it is not required for the statement to make sense.

Verification / Alternative check:
Replace 50% with 40% or 60%; the statement still stands. Thus II is not essential, confirming only I is implicit.

Why Other Options Are Wrong:
Only II: too specific. Either/Both: overreach. Neither: denies the early-year importance implied.

Common Pitfalls:
Confusing supportive data with assumptions. Necessary ≠ numeric detail.

Final Answer:
Only Assumption I is implicit.