Select the option that represents the given sentence in reported speech:

Priya said to Dilip, “ I always had this plan in my mind”.

’Said to’ must be changed to ‘told’. ‘this plan’ must be changed to ‘that plan’. First person pronouns must be changed to third person pronouns.

Also, the given sentence is in the simple past tense. ‘Had’ has been used to indicate possession. Therefore, the reported form must be in the past perfect tense.

”Priya told Dilip that she always had had that plan in her mind” is the correct answer. Hence, option C is the right answer.