R1, an ABR between backbone area 0 and area 1, has intra - area routes in area 0 for 10.1.1.0/24,10.1.2.0/24, and 10.1.3.0/24. These routes have metrics of 21, 22, and 23, respectively. An engineer then adds the area 0 r ange 10.1.0.0 255.255.0.0 command under the OSPF process of R1. Which of the following is true?（）

• A、R1 loses and then re - establishes neighborships with all neighbors.
• B、R1 no longer advertises 10.1.1.0/24 to neighbors into area 1.
• C、R1 advertises a 1 0.1.0.0/16 route into area 1 with a metric of 23 (largest metric).
• D、R1 advertises a 10.1.0.0/16 route into area 1 with metric of 21 (lowest metric).