Statement: It is desirable to put the child in school at the age of 4 or so.
Assumptions:
I. At that age the child reaches an appropriate level of development and is ready to learn.
II. The schools do not admit children after 5 years of age.
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Only I is implicit
An assumption is something the speaker takes for granted in making the statement; without it the statement would not make sense.
Assumption I is implicit. Advising school at about 4 makes sense only if the speaker believes a child of that age is developed enough and ready to learn.
Assumption II is not implicit. The statement says 4 is a desirable age, not the last possible one; it says nothing about schools refusing children after 5.