Special embeddings of some disconnected graphs into Euclidean space

This work considers such embeddings of graphs to $\mathbb{R}3$, that each line contains minimal number of points of the image. It is proved that for every embedding of graph containing disjoined union of two Kuratovski–Pontryagin graphs there exists a line containing four points of the image or more. So disjoint unions of Kuratovski–Pontryagin graphs are minimal $3$-unembedd able graphs.