Which of the following BEST explains why the natural family planning method should be used by long-term couples only?

Natural family planning involves tracking fertility and avoiding unprotected sex during fertile days, but it can fail if cycles are misjudged or the method is not followed consistently. Couples using it should be prepared for the possibility of an unintended pregnancy, which makes being in a stable, long-term relationship important. The best answer is “This method requires the couple to be prepared for a child.”

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