Which of the following lipids is found exclusively in mitochondria?
Cardiolipin Is a Major Lipid of Mitochondrial Membranes
Phosphatidic acid is a precursor of phosphatidylglycerol, which in turn gives rise to cardiolipin. This phospholipid is found only in mitochondria and is essential for the mitochondrial function. Decreased  cardiolipin levels or alterations in its structure or metabolism cause mitochondrial dysfunction in aging and in pathological conditions including heart failure, hypothyroidism, and Barth syndrome (cardioskeletal myopathy).
HARPERS ILLUSTRATED BIOCHEMISTRY30th ed, Page No:343
Cephalin
Phosphatidylserine
Cardiolipin
Phosphatidylinositol