The line in the table that correctly describes the trends going from hexanoic acid to butanoic acid is this: B
What is the trend?
Hexanoic acid has a formula mass of 116 g/mol, while butanoic acid has a formula mass of 88 g/mol. This means as the number of carbon atoms in the chain decreases, the formula mass of the molecule also decreases.
Hexanoic acid has a water solubility of around 1.1 g/100 g water, while butanoic acid is miscible with water in all proportions. This means as the carbon chain gets shorter, the carboxylic acid group becomes more dominant, making the molecule more polar and thus more soluble in water.