No, it was not really voluntary if the animals did not volunteer than he/she would have their food rations reduced by half(or barley enough to survive off of). I don’t have a quote sorry
Dogs and cats and cows and cates
It gives color to the festival and the variety of musical forms, styles, repertoires, and traditions that exist mirror the rich diversity in Filipino culture.
The sentence whose style is most appropriate with respect to clarity and simplicity of language is the first one - For centuries, art admirers have been digging through records of the painting to figure out its meaning.
The other sentences use language that is quite complicated.