The tRNA molecules deliver amino acids to the ribosome. It is able to connect to the mRNA by matching the _ to the _. The amino acids bond together with a _bond.

since there are no options posted i'll give you a few examples.

a dolphin's flipper, bird's wing, cat's leg.

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.