<span>The function which has a constant halving time is in the following form </span>
Where: A₀ is the <span>initial amount h is the half life time or the halving time. </span><span> t is the time </span> A(t) <span>the amount<span> that remains at time t </span></span> The previous function represents an Exponential decay<span> function. </span>
so, The correct answer is option B. <span>Exponential decay</span>