Step 1: Understanding the sentence.
The sentence is about an order given by the father. The key aspect here is that it's a command and the verb "ordered" indicates a strong directive. The reported speech must reflect the direct command.
Step 2: Analyzing the options.
(A) His father said, "Go to your room and study." This is correct as it reflects the direct command, maintaining the tone of an order.
(B) His father said to him, "Go and study in your room." This option is incorrect because it changes the original meaning by adding "and study" in the wrong order.
(C) His father shouted, "Go right now to your study room." This option changes the tone unnecessarily by introducing "shouted" and the urgency of "right now," which was not in the original sentence.
(D) His father said firmly, "Go and study in your room." This is incorrect because it adds a tone of firmness that is not present in the original sentence.
Step 3: Conclusion.
The correct answer is (A) His father said, "Go to your room and study." as it accurately captures the command in direct speech.