Step 1: Plan:
We take the two statements one at a time. If the Reason fails, the question is settled quickly.
Step 2: Assertion:
Bengaluru is well known as a hub for IT and electronics. This is a fact, so the Assertion holds.
Step 3: Reason:
The Reason gives the port as the main cause. A look at the map shows that Bengaluru lies in the interior of Karnataka, far from the coast.
Software and electronics products are light and can be sent by air or road, and these industries depend on trained people more than on ports. So the Reason is not correct.
Step 4: Choose:
True Assertion plus false Reason is option C. Options A and B accept the Reason, and option D rejects the Assertion, so none of them can be right.
Final Answer:
Option C is correct.
\[ \boxed{\text{C. A is true, but R is false}} \]