Statement–Assumption — “Success and failure are parts of every individual’s life and career.” Assumptions: I. The speaker truly knows the lives of average people. II. This statement will encourage those who have failed.

Introduction / Context:
The sentence is a general maxim claiming universality of ups and downs. Our task is to check whether it presupposes expertise about people’s lives or a guaranteed motivational impact.

Given Data / Assumptions:

• The statement is normative/descriptive wisdom, not an evidence report.
• It does not promise therapeutic effect; it is a perspective.

Concept / Approach:
Generalizations can be offered without personal knowledge of “average” lives (they may be philosophical or proverbial). Likewise, whether it motivates listeners is an outcome, not a necessary premise.

Step-by-Step Solution:
1) Assumption I: The content can stand as a widely accepted truism without the speaker proving knowledge of everyone’s life; thus I is not required.2) Assumption II: Even if nobody feels encouraged, the statement’s truth-claim remains; II is unnecessary.

Verification / Alternative check:
Maxims like “change is constant” do not rely on who utters them or on their psychological effect.

Why Other Options Are Wrong:
I-only/II-only/Either/Both impose extra commitments (expertise or motivation) beyond the statement’s scope.

Common Pitfalls:
Assuming every general statement must imply authority or intent to console.

Final Answer:
if neither I nor II is implicit.