In which of the following plants, the gynoecium is described as neither apocarpous nor syncarpous.

In pistils with only one carpel, the gynoecium is described neither as syncarpous nor apocarpous. Pea has single carpel in its flower. Hence its gynoecium is neither syncarpous nor apocarpous. If more than one carpels are found, the pistil is described as either apocarpous or syncarpous.