For example in a K-9 dog unit, the dog might not be allowed to eat until its duties were performed. Once ready the policeman signals (is signalling) the dog to eat--probably by a hand gesture. I signal my dogs all the time with hand gestures---although they pay little attention.
There are two types of accents. Sfaradi and Ashkenazi. The latter is common in Jerushalem and the former in most of the rest of the country, such as Tel-Aviv. You are exposed to both. With the sfaradí accent the r is said a lot like Spanish, or Italian, though only trilled once regardless of the place in the word. The r is softer in the Askenazi accent, more like a French r. Both are correct. I find the Sfaradí accent infinitely easier myself, but forms of pronunciation are equally correct.
Yes, לכלב is to the dog. My theory (trying to second-guess what was in the mind of the person who created this exercise) is that they were thinking: If it was "the policeman is telling the dog to eat", in English we use word order alone, but in Hebrew it would be השוטר אומר לכלב . (Or if he was telling the dog a story, in English the position of "the dog" shows that it's the indirect object, but in Hebrew השוטר מספר לכלב סיפור ) So by analogy, if the cop is telling the dog by means of a signal instead of using words, they thought it would be all right to dispense with "to" in the English, but the Hebrew version retains the -ל . Or maybe I'm overthinking this?