What is fermented grape juice?

What is fermentation ?

Match list I with list II. {:("List I","List III"),("Raw material","Product obtained"),("A)Germinated barley malt","(1) Wine"),("B) Fermented sugarcane","(2) Toddy"),("C) Fermented sap of palm tree","(3) Rum"),("D) Fermented grape juice ","(4) Beer" ):}

What is the fermented sap of palms? How it is collected? Explain the products obtained from it?

The hydrogen ion concentration of a fruit juice is 3.3xx 10^(-2) M . What is the pH of the juice ? Is it acidic or basic ?

Dough for idli and dosa is fermented by this organism _______