Attraction happens only when there are two or more unlike charges. Electric field lines appear to start from positive charge and end at negative charge.
In case (a), the field line start start at one charge and end at the other. This implies they are opposite charges and hence get attracted. In (b), the lines do not form closed loops. In other words, the field lines do not start at one charge and end at the other. This corresponds to repulsion. In (c), the field lines appear to start from one line of charge and end at the other line of charge. Hence, there will be attraction. In (d), the field lines appear to start from the line of charge (or ring) and end at the ring (or line of charge). Hence, they get attracted.
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