is the selective bulbous enlargement of the distal segment of a digit and is commonly associated with diseases that interfere with oxygenation of the blood.

Clubbing is the selective bulbous enlargement of the distal segment of a digit and is commonly associated with diseases that interfere with oxygenation of the blood.

Explanation:

Clubbing is defined as the bulbus enlargement of the terminal phalanges due to proliferation of connective tissue between fingernail and bone.

It is commonly associated with the cases that interfere with the oxygenation of the blood as mentioned below the causes of clubbing :

1) Cyanotic Heart disease

2) Cystic fibrosis

3) Lung cancer

4) Lung Abscess

5) Ulcerative collitis

6) Bronchiectesis

7) Benign mesothelioma

8) Infective endocarditis

9) Idiopathic pulmonary fibrosis

10) Neurogenic tumors

11) Gastrointestinal discomfort

d. planting trees

the trees take in carbon to make oxygen.

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

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