Directions: For the Assertion (A) and Reason (R) given below, choose the correct alternative. Assertion (A): The Indian Constitution came into force with effect from 26th January 1950. Reason (R): 26th January is celebrated as the Republic Day.

Introduction / Context:
This question checks basic civics knowledge about the date on which the Constitution of India came into force and why 26th January is significant as Republic Day. It also tests whether the student can distinguish between a factual consequence and a true explanatory cause in an assertion–reason format.

Given Data / Assumptions:

• Assertion (A): The Indian Constitution came into force with effect from 26th January 1950.
• Reason (R): 26th January is celebrated as the Republic Day.
• We assume standard NCERT style civics and history content about the Constitution of India and national days.
• The task is to judge the truth of each statement and decide whether R correctly explains A.

Concept / Approach:
The assertion states the key constitutional date. The reason states a national celebration associated with that date. In assertion–reason questions, even if both statements are true, R is considered the correct explanation of A only if it answers the “why” behind A. Here we must check: did the Constitution come into force on 26 January because that date is Republic Day, or is it the other way round: the date became Republic Day because the Constitution came into force then?

Step-by-Step Solution:
Step 1: Check Assertion (A). The Constitution of India was adopted on 26th November 1949 and came into force on 26th January 1950. Therefore, A is a correct factual statement.Step 2: Check Reason (R). 26th January is indeed celebrated every year as Republic Day in India, marking the date when India became a full republic by putting the Constitution into effect. So R is also a correct statement.Step 3: Examine the explanatory link. The Constitution did not come into force on that date because it was Republic Day. In fact, 26th January was chosen as the date for enforcing the Constitution due to its historical importance related to the 1930 declaration of Purna Swaraj (complete independence). After the Constitution came into force on that date, 26th January then became India national Republic Day.Step 4: So while both statements are true, R is not the logical reason that explains A. R describes a consequence or associated fact, not the cause behind the date chosen for enforcement.

Verification / Alternative check:
If R were a correct explanation, rephrasing would make sense as “The Constitution came into force on 26th January 1950 because that day is Republic Day.” This is reversed logic. Historically, the day is celebrated as Republic Day because the Constitution came into force on that date, not the other way around. This simple reversal test confirms that R is not the explanation for A.

Why Other Options Are Wrong:
Option a claims that R correctly explains A, which is incorrect because it mixes up cause and effect. Option c suggests that R is false, which contradicts the well-known fact of Republic Day. Option d says A is false and R is true, which is also wrong because the Constitution did come into force on 26th January 1950.

Common Pitfalls:
Students often mark option a whenever both statements are true, without carefully checking the direction of explanation. Another common error is to overlook prior events like the 1930 Purna Swaraj resolution, which gives deeper context to the choice of date. Always test whether R genuinely answers the “why” of A.

Final Answer:
Both statements are true, but Reason (R) is NOT the correct explanation of Assertion (A).