Refer to the aluminium-magnesium (Al-Mg) phase diagram below which is adapted to include labels of various invariant points (viz. A, B, C, D, and E). Which of these point(s) are classified as congruent phase transformations? (Hint: Congruent phase transformations are transformations in which there is no change in composition of the phases involved). Select all that apply. 

Verwys na die aluminium-magnesium (Al-Mg) fasediagram hieronder wat aangepas is om byskrifte van verskeie onveranderlike punte (nl. A, B, C, D en E) in te sluit. Watter van hierdie punt(e) word as kongruente fasetransformasies geklassifiseer? (Wenk: Kongruente fasetransformasies is transformasies waarin daar geen verandering in samestelling van die betrokke fases is nie). Kies alles wat van toepassing is.

Image source / Beeld bron: Binary Alloy Phase Diagrams, Second Edition ASM International, 1996