Assertion–Reason (Evaluate which reason(s) truly explain the assertion)\nAssertion (A): The average weight of an urban person has witnessed an increase over the past few decades.\nReason (R1): Food is available in abundance.\nReason (R2): Intake of foods rich in fats and refined cereals, combined with a sedentary lifestyle, has become a trend.\nWhich option best explains whether R1 and/or R2 are the reasons for A?

Introduction / Context:
Urban weight gain is typically multi-factorial, but exam questions of the Assertion–Reason type ask whether the proposed reasons directly and plausibly account for the assertion. Here, we must examine whether abundance of food (R1) and/or a specific dietary pattern plus sedentary lifestyle (R2) serve as reasons for rising average urban weight.

Given Data / Assumptions:

• Assertion: Average urban weight has increased over decades.
• R1: Food is available in abundance.
• R2: Diets trend toward high-fat/refined foods, and lifestyles are more sedentary.
• No additional constraints or time/place qualifiers beyond “urban” and “past few decades.”

Concept / Approach:
Weight gain (long-run) follows from sustained positive energy balance: calories in > calories out. Abundance (R1) is a contextual enabler but does not by itself force higher intake. In contrast, R2 directly addresses both sides of the energy-balance equation: higher-calorie, lower-satiety foods (intake) and reduced physical activity (expenditure), which jointly increase the probability of sustained caloric surplus.

Step-by-Step Solution:

Verification / Alternative check:
Populations with abundant food but high activity or whole-food diets may avoid weight gain; conversely, populations with ultra-processed, high-fat/refined diets and sedentary routines show rising average BMI—consistent with R2.

Why Other Options Are Wrong:
Option A over-credits abundance. Option C wrongly claims both are reasons; R1 is too general. Option D denies clear causal pathways from R2.

Common Pitfalls:
Confusing availability with consumption; assuming abundance guarantees overeating.

Final Answer:
If only reason 2 (R2) and not reason 1 (R1) is the reason for the assertion (A).