The correct answer is option D. "a claim". A claim is defined as a statement of something without providing evidence or any reference to support it. In this case the phrase "Drivers must avoid texting" is presented without any evidence or reference, which makes it a claim.
Claim means "to maintain as true". In law perspective, a claim means an interest in, as in a possessory claim, or right to possession, or the claim on the basis of which a person may be considered as a victim. Since traffic police strictly prohibits the use of mobile phones during driving so it is a claim on the basis of which the driver may be considered as a victim if he breaks the law.
