The correct answer is option 4: partial root parasite.

A partial root parasite is a type of plant that has the ability to partially obtain nutrients and water from the host plant through its roots. The parasitic plant forms a connection with the host plant`s roots and draws resources from it, but it can also photosynthesize and obtain some nutrients through its own leaves.

In the case of the Sandalwood tree, it is considered a partial root parasite because it forms connections with the roots of other plants in its ecosystem, allowing it to acquire some of the nutrients and water it needs to survive. However, it can also perform photosynthesis and produce its own food through its leaves.

It is important to note that the Sandalwood tree is not a total root or stem parasite, as it does not solely rely on the host plant`s roots or stem for its survival. It has the ability to obtain nutrients from the host plant`s roots, but it also has its own means of obtaining energy through photosynthesis.