4-bit ripple adder — compute the binary sum from given A, B, and initial carry A 4-bit adder has inputs C0 = 0, A1 = 0, A2 = 1, A3 = 0, A4 = 1 and B1 = 0, B2 = 1, B3 = 1, B4 = 1 (index 1 = LSB). Determine the 5-bit output (carry out concatenated with 4-bit sum).

Introduction / Context:
Understanding bit ordering and initial carry is essential when interpreting multi-bit adder problems. Here, you are asked to compute the result of adding two 4-bit numbers with an initial carry-in of zero and report the 5-bit result (carry out plus sum).

Given Data / Assumptions:

• Bit indices: A1/B1 are least significant bits (LSB), A4/B4 are most significant bits (MSB).
• C0 (carry-in) is 0.
• Output format is Cout S4 S3 S2 S1 as a 5-bit string.

Concept / Approach:
Form the two 4-bit numbers from the given bits: A = (A4 A3 A2 A1) and B = (B4 B3 B2 B1). Add them as unsigned integers with the carry-in. Convert the decimal sum back to binary; include final carry as the leftmost bit.

Step-by-Step Solution:
Construct A: A4=1, A3=0, A2=1, A1=0 → A = 1010₂ = 10₁₀.Construct B: B4=1, B3=1, B2=1, B1=0 → B = 1110₂ = 14₁₀.Add with C0=0: 10 + 14 = 24.Convert 24 to binary: 24 = 11000₂ (5 bits already show carry position).Thus the reported 5-bit output is 11000.

Verification / Alternative check:
Perform column-wise binary addition with carries: 0+0=0 (carry0), 1+1=0 carry1, 0+1+carry1=0 carry1, 1+1+carry1=1 carry1, final carry=1 → result 11000.

Why Other Options Are Wrong:
Other options correspond to arithmetic errors or misinterpreting bit order and carry concatenation (e.g., missing the final carry bit or reversing bit significance).

Common Pitfalls:
Confusing index order (A1 as MSB), omitting carry-out from the reported result, or misreading one of the provided bits.

Final Answer:
11000