To solve this problem, we need to identify which option is not a method of ex situ conservation. Let's analyze each option:$\newline \bullet$Option 1: In vitro fertilization$\newline$ - In vitro fertilization is a technique where egg cells are fertilized by sperm outside the body.$\newline$ - This is a method of ex situ conservation as it involves conservation outside the natural habitat.$\newline \bullet$Option 2: National Parks$\newline$ - National Parks are protected areas established to conserve wildlife and natural resources in their natural habitat.$\newline$ - This is a method of in situ conservation, not ex situ.$\newline \bullet$Option 3: Micropropagation$\newline$ - Micropropagation is a method of rapidly multiplying plant material to produce a large number of progeny plants using modern plant tissue culture methods.$\newline$ - This is a method of ex situ conservation.$\newline \bullet$Option 4: Cryopreservation$\newline$ - Cryopreservation involves preserving cells, whole tissues, or any other substances susceptible to damage caused by chemical reactivity or time at very low temperatures.$\newline$ - This is a method of ex situ conservation.$\newline$Based on the analysis, the option that is not a method of ex situ conservation is:$\newline$Option 2: National Parks$\newline$Therefore, the correct answer is Option 2.