Directions: Select the most appropriate filler(s) for the blank(s) such that the sentence makes coherent sense.

Although the warring parties had settled a number of disputes, past experience made them ________ to express optimism that the talks would be a success.

'Although' sets up a contrast between what has occurred 'success on some issue' and what can be expected to occur 'success for the whole talks'. Hence, the parties are reluctant to express optimism. The simple and common word “reluctant” is not offered as an answer choice, but a synonym 'reticent' is. Hence, (4) is the answer.