A party may direct no more than 50 interrogatories, in one or more sets, to any other party, except upon leave granted by the Court for good cause shown or by agreement of the other party. Interrogatory parts and subparts shall be counted as separate interrogatories for purposes of this rule.
There shall be sufficient space following each interrogatory in which the respondent may state the response. The respondent shall:
Each interrogatory shall be answered separately and fully in writing under oath, unless it is objected to, in which event the reasons for objection shall be stated in lieu of an answer. An objection to an interrogatory shall be made by stating the objection and the reason therefor either in the space following the interrogatory or following the restated interrogatory. The answers are to be signed by the person making them, and the objections signed by the attorney making them. The party upon whom the interrogatories have been served shall serve a copy of the answers, and objections if any, within 30 days after the service of the interrogatories, except that a defendant may serve answers or objections within 45 days after service of the summons and complaint upon the defendant. The court may allow a shorter or longer time. The party submitting the interrogatories may move for an order under Rule 37(a) with respect to any objection to or other failure to answer an interrogatory.
An interrogatory otherwise proper is not necessarily objectionable merely because an answer to the interrogatory involves an opinion or contention that relates to fact or the application of law to fact, but the court may order that such an interrogatory need not be answered until after designated discovery has been completed or until a pretrial conference or other later time.
N.C. Gen. Stat. § 33