Statement: “You must learn to refer to a dictionary if you want to become a good writer,” A advises B. Assumptions: I. Only writers refer to a dictionary. II. All writers (good or bad) refer to a dictionary. Choose the option that identifies which assumption(s) is/are implicit.

Introduction / Context:
The advice links dictionary use with improved writing quality. It does not claim exclusivity or universality of dictionary use across all writers.

Given Data / Assumptions:

• Dictionary consultation is recommended as a means to improve.

Concept / Approach:
Necessary assumptions: “Using a dictionary helps writing.” Neither I (only writers use it) nor II (all writers use it) is required.

Step-by-Step Solution:
I is unnecessary: non-writers can also use dictionaries.II is unnecessary: some good writers may seldom consult dictionaries; the advice remains sensible.

Verification / Alternative check:
The advice holds if dictionary use is helpful, not if it is exclusive or universal.

Why Other Options Are Wrong:
Options including I or II add claims the statement never presupposes.

Common Pitfalls:
Confusing a recommended aid with a universal practice.

Final Answer:
if neither Assumption I nor Assumption II is implicit