1. A tag responsive to queries from a reader, the tag comprising: an antenna; an Integrated Circuit (IC) coupled to the antenna, the IC configured to receive from the reader a first query command comprising a first value of a probability parameter and a first state flag for the tag, the IC configured to receive a second query command comprising a second value of a probability parameter and a second state flag for the tag, wherein the tag is configured to determine if the state of the tag matches to one of the first state flag or the second state flag, and the IC configured to reply to the first query command according to the first value of the probability parameter and to ignore the second query command, if the state of the tag matches to the first state flag, wherein the IC is configured to reply to the second query command according to the second value of the probability parameter and to ignore the first query command, if the state of the tag matches to the second state flag.