Calendars — On which date is Amit's birthday in September 2010? Statements: I. In September 2009, his birthday fell on the last Thursday of the month. II. In September 2010, his birthday will fall on the last Friday of the month.

Introduction / Context:
We need the exact date (calendar date number) of Amit's September 2010 birthday using weekday placement information.

Given Data / Assumptions:

• II provides that in Sep 2010 the birthday is on the last Friday.
• Month/year are fixed (September 2010 has 30 days).
• I references Sep 2009, which is not required if II already pins the weekday position within Sep 2010.

Concept / Approach:
For a fixed month/year, the phrase 'last Friday' corresponds to a unique date.

Step-by-Step Solution:

Verification / Alternative check:
Calendar enumeration confirms a single 'last Friday' date exists for any specified month/year.

Why Other Options Are Wrong:

• A/C/E/D: II alone suffices; I is superfluous.

Common Pitfalls:
Thinking the previous year's weekday is required; it is not when the target month/year is explicit.

Final Answer:
B — Statement II alone suffices (unique 'last Friday' date in Sep 2010).