Black wood is obtained from
A. Dalbergia
B. Albizzia
C. Manihot
D. Salvia

Hint:-Blackwood is a hardwood. The timbers of blackwood can be used to make furniture, panels and decorative pieces. This kind of wood is sold at very high prices in markets. Blackwood can be obtained from Australia and Africa. However, blackwood from these countries are obtained from different plant species.

Complete step-by-step solution:-
Blackwood is an extensively branched tree. Their timber is jet black in colour, hence the name. The tree is semi deciduous with small clustered flowers that are white in colour.
Dalbergia belongs to the genus Fabaceae. It is a deciduous plant found in Africa. The Dalbergia melanoxylon is associated with African blackwood. The timber of this tree is used to make musical instruments, furniture and decorative items. The timber of Dalbergia melanoxylon is very expensive owing to its hardness, machinability and moisture repellant nature. Various parts of the tree have a lot of medicinal uses, native to Africa. Therefore, Blackwood can be obtained from Dalbergia.
Albizzia belongs to the family Fabaceae. They are also known as Silk Plants. Albizia are shrubs or short trees with clustered flowers. These plants are native to east and south Asia. Albizzia can be consumed orally to treat anxiety, depression that may arise from cancers, insomnia. For its use to treat depression, Albizzia is also known as the Herb of Legal Happiness.
Manihot are monoecious trees that belong to the family Euphorbiaceae. Certain species of these plants have medicinal uses. The leaves are Vitamin B rich and can be consumed. The tubers of this plant are also consumable.
Salvia belongs to the family Lamiaceae. It is essentially the family of mints. The habitat range of plants of this genus is very wide. The uses of these plants are as decorative plants, and also as healing herbs. They can be used for cooking as well.
Hence, it can be concluded from the information elaborated above, that Blackwood is obtained from Dalbergia.
Hence, option (a) is correct.

Note:- African Blackwood is obtained from Dalbergia. The timber of these plants is known for their hardness, and is sold at very high prices. Blackwood timber is used to make musical instruments, decorative furniture. Another type of Blackwood is found in Australia and obtained from Acacia species.