A. 4-bit
B. 8-bit
C. 16-bit
D. 32-bit

Solution

B. 8-bit

Explanation

<p>The 8051 has an 8-bit data bus, meaning:</p><ul><li>It processes 8 bits of data at a time.</li><li>The accumulator, registers, and ALU are all 8-bit.</li></ul><p>It can access 8-bit data in memory and perform 8-bit arithmetic/logical operations.</p>