Step 1: Understanding the Concept
The question asks about a specific architectural detail of the temple platform (`jagati`) as prescribed in the Viṣṇudharmottara Purāṇa. `Bhūmikās` in this context refers to terraces or levels.
Step 2: Textual Reference
The Viṣṇudharmottara Purāṇa is an important source for understanding the theory behind temple architecture. In its discussion of the temple plan and elevation, it specifies the ideal form for various parts. For the `jagati`, the raised platform upon which the temple stands, the text recommends that it be constructed with three terraces or levels (`tri-bhūmikā`). This tripartite division reflects cosmic symbolism prevalent in Hindu thought.
Step 3: Final Answer
The Viṣṇudharmottara Purāṇa prescribes that the `jagati` should consist of three `bhūmikās`.