The Baljet test is a qualitative chemical test used in pharmacognosy to detect the presence of glycosides in a sample. This test utilizes a sodium picrate solution, which reacts with glycosides to produce a distinct orange or red coloration, confirming their presence.

Let's break down the given options and understand why glycosides are the correct phytoconstituents identified by the Baljet test:

1. Glycoside: Glycosides are compounds where a sugar is bound to another functional group via a glycosidic bond. The Baljet test specifically targets glycosides, producing an orange or red color change when a sodium picrate solution is used, confirming its presence. Therefore, the Baljet test is positive for glycosides.
2. Tannin: Tannins are polyphenolic compounds that do not react with sodium picrate solution in the Baljet test. Hence, they cannot be confirmed by this test.
3. Chlorophyll: Chlorophyll is a green pigment found in plants responsible for photosynthesis. It does not react with sodium picrate, thus cannot be identified by the Baljet test.
4. Triterpene: Triterpenes are a class of chemical compounds composed of three terpene units. They also do not produce any color change with the sodium picrate solution, hence they are not detected by the Baljet test.

Based on the above explanations, the Baljet test is used specifically to confirm the presence of glycosides using sodium picrate solution.

Therefore, the correct answer is Glycoside.